Electric safety razor with stationary cap and improved electromagnetic drive means



July 1, 1969 D. H. HOLDT 3,452,435

ELECTRIC SAFETY RAZOR WITH STATIONARY CAP AND IMPROVED ELECTROMAGNETICDRIVE MEANS Filed Dec. 27, 1966 Sheet FIG 2 INVENTOR DONALD H. HOLDT BYfiw 0 A ATTORNEYS July 1, 1969 D. H. HOLDT 3,452,435

ELECTRIC SAFETY RAZOR WITH STATIONARY CAP AND IMPROVED ELECTROMAGNETICDRIVE MEANS 2 Sheet of 3 Filed. Dec. 27, 1966 INVENTOR DONALD H. HOLDTF/G: 6 BY WQ Q O 7/ F ATTORNEYS July 1, 1969 D. H. HOLDT 3,452,435

ELECTRIC SAFETY RAZOR WITH STATIONARY CAP AND IMPROVED ELECTROMAGNETICDRIVE MEANS Filed D80. 27, 1966 1 Sheet 3 of3 FIG. 12 I00 INVENTORDONALD H. HOLDT ATTORNEYS 3,452,435 Patented July 1, 1969 US. Cl. 30-456 Claims ABSTRACT OF THE DISCLOSURE An electric safety razor having ahead unit on which a blade is mounted for reciprocatory movement in adirection parallel to its edges and a body portion for holding the headunit and for sealingly housing an alternating flux electromagnetic drivemeans. The blade reciprocates relative to a cap member and guard rollerswhich are stationarily mounted immediately above and immediately belowthe blade edge, respectively. The top of the body portion has a recessbetween the legs of the electromagnet, and a permanent magnet attachedto the blade extends into this recess to be driven by the electromagnet.

This invention relates to an electric safety razor having areciprocating blade, and more particularly to an electric safety razorwherein the safety razor is caused to be reciprocated by a power drivenmeans in a direction parallel to its cutting edges.

Electric safety razors of this general type are disclosed in US. Patentapplication Ser. No. 435,005, filed Feb. 24, 1965, now patent no.3,327,387, issued June 27, 1967, and US. patent application Ser. No.467,935, filed June 29, 1965, now Patent No. 3,321,831, issued May 30,1967.

Various problems have arisen in the use of previous razors of this type.First, the means for imparting reciprocatory end to end movement of therazor blade has not provided sufiicient power, as a result of which theeffectiveness of the razor blade has been impaired. The power drivenmeans normally includes an electric drive comprising an electromagneticcore contained in the handle of the razor and having an energizingwinding wound around one leg of the core. The magnetic polarity of thelegs, or poles, of the core alternates in accordance with the frequencyof the alternating current source supply. A conventional electric outletmay be used to provide the alternating current source. The head unit ofthe razor is normally provided with a permanent magnet which isreciprocated by means of the alternation of the polarity of the magneticflux between the poles of the core. The permanent magnet is connectedthrough various means to the blade which is thereby reciprocated in adirection parallel to the edges of the razor blade. However the previouselectric razors have been unsatisfactory since the permanent magnet hasbeen spaced from the direct path of the magnetic flux between the polesof the electromagnetic core, as a result of which the driving force hasbeen relatively weak. The force driving the permanent magnet has beenespecially weak when the permanent magnet is positioned at the endlimits of its travel. Therefore the blade has not been reciprocated withsuflicient force and has therefore been inadequate in use.

A second disadvantage of the previous razors has been that the blade capmounted on the head unit above the razor blade has been reciprocatedtogether with the blade relative to the stationary guard rollers causingthe skin to move with the razor blade. This minimizes the cutting andshearing effectiveness of the blade, and results in uncomfortable andinefiicient shaves.

The electric razor of the present invention overcomes the deficienciesof prior electric razors, is more simple and economical to manufacture,and provides an eminently more satisfactory shaving device. The improvedblade drive means provides a more powerful drive, significantlyimproving the operation of the razor. Th electric drive is whollycontained in the waterproof and moistureproof handle of the razor. Amore powerful drive is obtained by inserting a portion of the drivenpermanent magnet of the razor, which is contained in the head unit, intothe direct flux path between the poles of the electrically excitedelectromagnetic core. This has been accomplished by providing a recessin the upper surface of the handle between the poles of theelectromagnetic core and thereafter positioning a portion of the drivenpermanent magnet into the recess. Since a portion of the permanentmagnet is thereby inserted in the main flux area of the core, it isdriven in a more positive manner. The upper surface of the handle belowthe recess fully seals the electromagnetic core and the remainingportions of the electric drive from both water and moisture. Thus thereis no open electrical structure and there is no danger of an electric.shock when using the electric razor of this invention. The razor cantherefore be used on a dry skin surface; or the skin may be lathered, ifdesired, without fear that the user will receive an electric shock.

In the razor blade of this invention both structural members adjacentthe blade edges and touching the skin are held stationary while theblade is reciprocated relative to the two stationary structural members.The blade cap which touches the skin above the blade edge is pivotallyconnected to the guard rollers which contact the skin below the bladeedge and the razor blade is caused to reciprocate between the guardrollers and the cap. Thus in the present razor, unlike the previousrazors, the cap no longer reciprocates with the blade. Both the cap andthe guard rollers prevent movement of the shavers skin and thereby allowthe reciprocating blade to cut with maximum effectiveness. The cap ispivotally connected to the shaft ends of one guard roller and pivotsabout the axis of that guard roller. The cap is further provided withprotuberances which are received in recesses in the shaft ends of theother guard roller. The cap is therefore pivoted about the shaft ends ofone guard roller and is adapted to be snapped into operative positionreleasably engaging the shaft ends of the other guard roller. Thus thestationary cap and guard rollers enable the blade to function moreeffectively and allows the user to get a more efficient and morecomfortable shave.

It is, therefore, an object of my invention to provide an improved drivemeans for an electric razor which will enable the user to get a moresatisfactory shave.

It is a further object of my invention to provide a nonreciprocatingskin contacting cap member for an electric safety razor which cooperateswith non-reciprocating skin contacting members to provide a moresatisfactory shave.

Still another object of my invention is to provide a drive means whereina portion of a permanent magnet is placed in the direct magnetic fluxpath between the poles of an electromagnetic core and wherein theelectrically driven core is totally insulated from the driven permanentmagnet by a moisture proof cover.

A further object of this invention is to provide a stationary skincontacting cap member which is mounted above a reciprocating blade andwhich is easy to assemble and reliable to use.

Other objects and novel features of this invention will appear morefully hereinafter from the following detailed description of theinvention when taken in connection with the accompanying drawingswherein:

FIG. 1 is a perspective view of the electric safety razor constructed inaccordance with the principles of this inventlon;

FIG. 2 is a partial side view showing the head portion of the razor;

FIG. 3 is a partial end view of the head portion of the razor;

FIG. 4 is a partial perspective view showing the cap member of the razorin a pivoted inoperative position;

FIG. 5 is a partial section view of the razor head taken along line 5-5of FIG. 3;

FIG. 6 is a partial section view of the razor head taken along line 66of FIG. 2;

FIG. 7 is a partial section view taken along line 77 of FIG. 3 showingthe releasable connection of the cap member to a guard roller;

FIG. 8 is a partial section view taken along line 8-8 of FIG. 3 similarto FIG. 7 showing the cap member similar reference characters refer tosimilar parts throughout the several views, an electric safety razorindicated generally by 10, comprises a body portion in the form of ahandle 12 which houses the electric drive and is provided with aremovable head unit 14. The head unit 14 is removably supported on thehandle 12 by means which I provide for firm interengagement between thehead 14 and the handle 12.

The head unit 14 comprises a support member 16 having a pair of upwardlyextending shoulders 21 and 23 and a pair of downwardly extendinggripping members 18 and 20 formed integrally therewith. The grippingelements 18 and 20 frictionally retain the support member 16 securely onthe handle 12 and substantially prevent relative movement between themember 16 and the handle 12. The handle 12 has upwardly projectingholding members 22 with laterally projecting outer edges 25, which arelocated adjacent the interior of the downwardly extending grippingelements 18 and 20 to frictionally retain the support member 16 securelyon the handle 12. A second retaining means is provided for preventingmovement of the head 14 relative to the handle 12. To this end,referring to FIG. 6, the holding members 22 are provided with grippingrecesses 28 which cooperate with a pair of inwardly bent shoulders 26 onthe head unit 14.

The top portions of the holding members 22 are beveled at 27. Uponattachment of the head unit 14 on the handle 12 the bent shoulders 26 ofthe support member 16 ride along the beveled surfaces 27 causing theholding members 22 to move inwardly. Upon alignment of the bentshoulders 26 with the recess 28, the holding members 22 snap to theirnormal position and securely hold the head unit 14 on the handle 12.Thus, the head unit 14 is securely retained on the handle 12 by both thefrictional gripping of the elements 18 and 20 with the outer edges ofthe holding members 22 and the intercooperation of the shoulders 26 andthe recesses 28.

To remove the head 16 from the handle 12, release members 24 on theresilient holding members 22 are pushed inwardly as a result of whichthe holding members 22 are moved inwardly and the recesses 28 are movedout of engagement with the bent shoulders 26 of the head 14, thusallowing the head unit to be readily removed by the application of apulling force on head 14 sufficient to overcome the frictionalengagement between gripping elements 18 and 20 and projecting edges 25.

The upwardly extending shoulders 21 and 23 provide support means for apair of eccentrically mounted guard rollers 30 and 32. The operation andfunctions of the guard rollers 30 and 32 are fully set forth incopending application Serial No. 435,005, now Patent No. 3,327,387,referred to above. The guard rollers 30 and 32 have shafts 31 and 34respectively, extending outwardly from both ends thereof, said shaftsbeing integral with the guard rollers and being eccentrically mountedwith respect to the centers of said guard rollers. Openings are providedin the shoulders 21 and 23 of support member 16 which openings areadapted to receive the shafts 31 and 34, so that the rollers 30 and 32are rotatably mounted in support member 16 with the center of rotationoffset with respect to the centers of the guard rollers. Handles 36 and38 are provided for rotating the guard rollers 30 and 32, respectively.The handles 36 and 38 have projections which cooperate with spacedindentations 37 on the shoulder 21 to provide for incremental adjustmentof the position of rollers 30 and 32.

A blade carrier 40, a blade 42, and a blade retainer 44 are resilientlymounted by said support member 16 by means of double arm leaf springs 43for reciprocatory end to end movement in a direction parallel to thecutting edge of the razor blade as seen in FIG. 5.

The top ends of the springs 43 are connected to the blade carrier 40 bymeans of rivets 45 while the lower ends of the springs are secured togripping elements 18 and 20 of support member 16 by means of rivets 49.The spring elements 43 are preferably made of resilient metal so thatwhile the springs permit endwise reciprocatory motion they alsocooperate to substantially prevent any side-to-side motion. Bladecarrier 40 is positioned above the support member 16 and is mounted forreciprocatory end to end movement by means of the springs 43. The bladecarrying member 40 has two upwardly extending blade positioning prongs(not shown) which are positioned to receive the razor blade 42 andprevent movement of the blade relative to the blade carrying member 40.The blade carrier 40 has a pair of magnet retainers 48 extendingdownwardly therefrom. The retainers 48 have interior arcuate surfaces 50which are adapted to receive and frictionally retain a permanent magnet52 member.

The blade carrier 40 has an opening 54 which houses the blade holdingand ejecting spring member.

A blade retainer 44 is mounted over the blade 42 and has slottedopenings which receive the upper portion of the prongs of the bladeretaining member 40. The blade retainer 44 has a shaft 56 extendingdownwardly therefrom. The shaft has opposing cap retaining notches 58positioned near the base thereof. Positioned in said opening 54 in theblade carrier 40 is an off center Spring 60 which is retained in therecess 54 in the blade carrying member 40 by the rivets 45 which alsohold springs 43. The off center spring 60 has two gripping portions 61and 63 which grip the notches 58 on the shaft 56 of the blade retainer44 in order to bias the blade retainer and the blade downwardly intotheir operative position.

A spring 74 is utilized to move said 01f center spring 60 to releaseshaft 56. The support member 16 has a pair of openings 70 in thedownwardly extending gripping elements 18 and 20. The openings 70receive finger engaging, blade releasing members 72 therein. The bladereleasing members 72 are utilized to move the spring 74 upwardly,thereby moving the off center spring 60 upwardly, thereby releasing saidblade retainer 44 and said blade 42. The outer faces of members 72 areribbed at 73 to provide a finger gripping surface. The inner ends of themembers 74 are provided with arcuate recesses 76. The initiating spring74 is curled at its ends 75 and received in the recesses 76 of themembers 74. The operation and functions of the off center spring 60 andthe initiating spring 74 are fully set forth in copending applicationSer. No. 467,935, new Patent No. 3,321,831,

referred to hereinabove. Thus it can be seen that the off center spring60 and the initiating spring 74 provide an efficient means for ejectinga razor blade. Furthermore, the off center spring 60 grips the shaft 56of the blade retainer 44 and forces the blade retainer 44 against therazor blade 42 and the blade carrying member 40 thereby facilitaing themovement of said carrying member, said blade, and said blade, retaineras a single unit.

A cap member 80 is pivotally mounted on the head unit 14 above the bladeretaining member 44. A small clearance 81 is provided between the cap 80and the blade retainer 44 to allow the blade retainer to move lengthwiserelative to the cap without rubbing against said cap. The cap 80 has apair of downwardly extending connecting legs 82 near one side of the cap80 permanently rotatably afiixed to the razor head unit 14, and anotherpair of downwardly extending legs 84 adapted to removably engage saidrazor head unit 14 when the cap is in operative position. Thepermanently affixed legs 82 have holes 85 therein and said legs arerotatably connected to the shaft 34 of the roller 32, (see FIG. 8), andpermanently affixed to the head unit 14 by means of the handle 38 on oneend and any suitable locking means at the other end. For example theother end of the shaft 34 may be threaded to receive a threaded nut. Thelegs 82 are pivotable about the shaft 34 and are maintained in permanentengagement with the razor head number unit 14.

The legs 84 are adapted to engage the shaft 31 of the guard roller 30.The legs 84 have downwardly extending portions 86, outwardly extendingportions 87, and further downwardly extending portions 88. The portions88 are provided with inwardly facing protuberances 89 which are utilizedto attach the legs 84 to shaft 31. The ends of the shaft 31 are providedwith recesses 91. The protuberances 89 are adapted to snap into therecesses 91 when the cap 80 is in operative position as clearly seen inFIG. 7. The legs 84 are constructed of a resilient material. It canreadily be seen that the cap is pivotable about its connection with theshaft 34 of the guard roller 32 and is adapted to engage the shaft 31 ofthe guard roller 30 when the cap is in operative position. The cap '80may be moved from operative to inoperative position by pivoting it aboutits connection with the shaft 34 by the application of a light pressureon the cap. In operative position the cap 80 provides a stationarysurface for gripping the shavers skin and substantially preventsmovement of the shavers skin relative to the movement of thereciprocating razor blade 42. The cap 80 thereby cooperates with theguard rollers 30 and 32 to provide stationary members for engaging theshavers skin both above and below the plane of operation of the razorblade 42 and thus enables the shaver to get a more comfortable and amore satisfactory shave.

In order to provide an electrically operated drive for the reciprocatoryblade carrying member, blade, and blade retainer, the present inventionutilizes the permanent magnet member 52 which is held by the magnetretainers 48 which are connected to the blade carrier 40. The part ofthe motor forming the drive means for driving the permanent magnetmember 52 is housed in the handle 12 of the razor. As heretofore pointedout, the motor construction is such that no parts project throughopenings in the casing wall. More particularly, the motor constructionincludes an electromagnetic core 100 formed in a generally C-shape,having legs or poles 102 and 104 which are spaced apart to constitute anair gap 105. An energizing winding (not shown) is wound around one legof the electromagnetic core 100. The energization of the winding from analternating current source causes the pole pieces 102 and 104 toalternately become north and south poles in accordance with thefrequency of the source. Assuming that the lower end of the magnet 52 isa north pole and that at a particular instant the pole piece 102 is anorth pole and the pole piece 104 is a south pole, it will be readilyunderstood that the magnet 52 will be moved to the right as viewed inFIG. 9, because of the repelling and attracting magnetic forces actingthereon. Such movement will cause the blade carrier 40, the blade 42,and the blade retainer 44 to be also moved to the right with the respectto the guard rollers 30 and 32 and the cap 80, in a direction parallelto the cutting edges of the blade 42, this action being permitted by theresilient support of the blade carrier 40 by means of the springelements 43. During the other half cycle of current, the polarity of thepole pieces will be reversed, and the magnet 52, and parts connectedtherewith will be moved to the left in response to the repelling andattracting forces acting thereon. Thus it is readily seen that the bladecarrier 40, the blade 42 and the blade retainer 44 will reciprocate backand forth in a direction parallel to the blade edges, in accordance withthe frequency of the supply source, which results in an effectiveshearing or cutting action.

In order to apply the full effect of the attracting and repelling forcesof the poles 102 and 104 on the permanent magnet member 52, it has beenfound necessary to position the permanent magnet member 52 in the mainarea of flux; that is, in the direct flux path between the poles. Thus,as seen in FIGS. 10-12, this invention provides for inserting a portionof the permanent magnet member into the main flux area in order tocreate a more powerful and positive drive.

The electromagnetic core is seated in the handle 12 of the razor. Thetop surface 13 of the handle 12 is provided with a recess therein. Therecess is placed di rectly between the poles 102 and 104 of theelectromagnetic core 100 which permits positioning of a portion ofmagnet 52 in the direct flux path between the poles thereby providing amore powerful drive for the magnet, as explained above. Thus, the partsof the motor construction which must be physically connected with theelectrical source are completely within the handle 12 below the recessin the upper handle surface 13 (see FIG. 12).

A modification of the permanent magnet member 52v is shown in FIGS. 10and 12. The shape of the magnet member is therein modified at the bottomportion thereof to include a laterally extending portion 52 having a V-shaped cross-section to enable the recess to be made smaller. Comparerecess 110' in FIGS. 10 and 12 with recess 110 in FIGS. 5 and 11. Themagnet 52 is placed between the poles 102. and 104 and is in the mainflux area in this modification. The recess may be made of any desiredshape and the magnet may also be produced in any desired shape withoutdeparting from the spirit and scope of this invention.

Thus it is seen that a new and more powerful drive has been provided forreciprocating the blade assembly of this invention. The blade is drivenin an effective reciprocatory movement parallel to the edges of theblade in order to cut the desired material with a shearing action.

From the foregoing, it will be readily apparent that a highly efficientand greatly simplified electric razor construction has been provided bythe present invention. The particular type of motor drive employed, andthe arrangement of the parts thereof is such that a water tight casingor housing is provided, which eliminates all possibility of moisturedamage to the electric drive within the handle or electric shock to theuser. In operation, the razor is noiseless and durable since the movingparts are mounted with a clearance to avoid rubbing and slidingfriction. An important feature of the invention is the simplified andreadily pivotable cap which provides a stationary member whichcooperates with the guard rollers in order to provide two surfaces, oneabove and the other below the reciprocating blade, which preventmovement of the skin along with the reciprocating blade. A furtherdistinctive and novel feature includes the insertion of the permanentmagnet driven member into the main flux field of the electromagneticcore thereby providing a more direct and more powerful drive to theblade member.

The invention operates as follows. An alternating current is supplied tocore 100 thereby alternating the polarity of pole pieces 102 and 104,thereby causing the permanent magnet 52 to reciprocate in recess 110,first towards one pole, and then towards the other, and so on. Of courseas the magnet reciprocates it carries with it those elements with whichit is rigidly connected, namely the blade carrier 40, spring 60, bladeretainer 44 and, of course, blade 42. Meanwhile the remaining elementsof the head form a stationary portion of the head unit which does notpartake in the reciprocatory movement. This stationary portion wouldinclude, inter alia, support member 16, gripping elements 18 and 20,shoulders 21 and 23, rollers 30 and cap member 80.

While two embodiments of the invention have been shown and described, itwill be understood by those skilled in the art that many modificationsmay be made without departing from the spirit of the invention. It is tobe expressly understood however, that the drawings are utilized forpurposes of illustration only, and are not designed as a definition ofthe limits of the invention, references being had for this purpose tothe appended claims.

What is claimed is:

1. An electric safety razor comprising a body portion and a head unit,said head unit comprising a stationary portion which is held stationaryrelative to said body portion and a means for mounting a blade forreciprocatory movement relative to said stationary portion in adirection parallel to the blade edges, elongated roller elements mountedon said stationary portion, said mounting preventing the rollers fromreciprocating with the blade, and said rollers positioned immediatelybelow each blade to contact the skin of the user immediately below theblade edge, and a cap member mounted on said stationary portion abovethe blade, said mounting preventing the cap member from reciprocatingwith the blade and said cap member positioned such that its edgecontacts the skin of the user immediately above the blade edge, the edgeof the blade projecting outwardly beyond the edge of the cap between theroller elements and the edge of the cap member while undergoingreciprocatory movement parallel to its edges.

2. An electric safety razor as claimed in claim 1 including a bladecarrier for holding the blade and adapted to reciprocate therewith, andmeans for reciprocating the blade carrier and the blade relative to thestationary portion.

3. An electric safety razor as claimed in claim 2 including a bladeretainer positioned between the blade and the cap member for rigidlyholding the blade on the blade carrier, said blade retainer mounted toreciprocate with the blade and the blade carrier.

4. An electric safety razor as claimed in claim 1 wherein the cap memberis removably connected to said roller elements.

5. An electric safety razor as claimed in claim 1 wherein the cap memberincludes vertically extending legs, said legs removably engaging theouter ends of said roller elements so that the cap member is pivotableabout the axis of at least one roller element.

6. An electric safety razor comprising a body portion and a head unit,said head unit comprising a means for mounting a blade having cuttingedges for reciprocatoiy movement in a direction parallel to the bladeedges, and a cap member mounted on the head unit above the blade, saidmounting preventing the cap member from reciprocating with the blade,said cap member being positioned to contact the skin of the user abovethe blade and being stationarily mounted with respect to the said headunit, the said head unit further comprising roller elements positionedimmediately below each blade, said mounting preventing the rollers fromreciprocating with the blade, said rollers being positioned to contactthe skin of the user below the blade edge, and said cap member includingvertically extending legs, said legs, removably engaging the outer endsof said roller elements so that the cap member is pivotable about theaxis of at least one roller element.

References Cited UNITED STATES PATENTS 2,054,287 9/ 1936 Hartmann 30-452,105,855 1/1938 Caise 30-45 2,182,571 12/1939 Savary 30-83 2,301,14711/1942 Schaaf et al. 3045 2,530,759 11/1950 Collins et al. 30--452,609,602 9/1952 Harshberger 30-45 2,991,554 7/1961 Somers et a1. 3034.23,321,831 5/1967 Han et al. 3045 3,327,387 6/1967 Harr et al. 30-342FOREIGN PATENTS 835,413 3/ 1952 Germany.

MYRON C. KRUSE, Primary Examiner.

US. Cl. X.R. 30-342, 83

